is based on decennial census data from the U. S. Census Bureau
. The annual intercensus estimates are interpolated from the decennial data. Current population data is available from
- The Total Number of Representatives is the number authorized by Congress to represent the state. Note that the actual number representing the state at any given time may be a smaller due to vacancies (e.g., resignations, deaths, removal). Conversely, the total number of Representatives during any time span may be more than the authorized number due to turnover. The initial point in the graph is the first year that the state is admitted to the union. This data is available from the U.S. Census Bureau (e.g., “Table B”).
- The District Population Size is the total resident population (per the U. S. Census Bureau) divided by the total number of House Representatives actually authorized by Congress (by year for each state).
- The Minimum House District Size was established by the U. S. Constitution at 30,000 inhabitants.
- The hypothetical Maximum Number of House Representatives that could have been allocated is equal to the state’s total population divided by 30,000. For each decennial apportionment, this calculation is done in the ninth year of the decade (e.g., 1989) and is applied to the decade beginning the third year of the following decade (e.g., 1993 to 2002).
- Reelected Incumbents is the number of House seats occupied by Representatives who are reelected from the prior term.
- Reelected Representatives as a Percentage of Total is the number of Reelected Incumbents (footnote 6) divided by the Total Number of Representatives (footnote 2). Chart E graphs this for each Congress and cumulatively. For additional information on the analysis supporting Chart F see Correlation Analysis of House Representatives’
Reelection Rates vs. House District Sizes.
- Average Tenure in Office is the average number of years served consecutively by all the Representatives compressing any given Congress. Tenure is based on the consecutive number of terms a Representative is elected to office. This number is multiplied by two in order to arrive at the total number of years. For example, if the Representative serves only one term, then his duration is two years. If a Representative serves two consecutive terms, then his tenure is four years, and so forth. For additional information on the analysis supporting Chart G see Correlation Analysis of House Representatives’
Average Tenure vs. House District Sizes.